1. Field of the Invention
The present invention relates to an information processing apparatus, an information processing method, and a program.
2. Description of the Related Art
In recent years, advances have been made in the speed and capacity of data transfer on networks. One result is that a great amount of video has become easily available to a huge number of users at certain locations on networks. It has also become possible for many users to upload their own videos and share such content with others using video sharing sites. Although it has become easy to share large files such as videos, there is now a vast amount of content available, which makes it difficult for users to find content that matches their preferences and/or to judge whether content that has been uploaded is illegal.
One conceivable solution would be to introduce a system that inputs a video being viewed by the user and/or retail content already owned by the user and outputs other content that is similar. By using this type of system, it would be possible to automatically recommend other content and judge whether uploaded content is illegal, thereby making it unnecessary to manually manage a vast amount of content.
A number of inventions that relate to judging similarity between videos have been disclosed as listed below. For example, the first five of the following references relate to methods of measuring similarity between video images using information obtained from an “image part” of a video.    Japanese Laid-Open Patent Publication No. 2002-203245 (Japanese Patent No. 3711022)    Japanese Laid-Open Patent Publication No. 2006-285907    Japanese Laid-Open Patent Publication No. 2009-147603    Japanese Laid-Open Patent Publication (Translated PCT Application) No. 2006-514451    Japanese Laid-Open Patent Publication No. 2002-32761 (Japanese Patent No. 3636674)    Japanese Laid-Open Patent Publication No. 2009-70278    Japanese Laid-Open Patent Publication No. H11-308581 (Japanese Patent No. 3569441)
The technologies listed above use movement recognition or luminance measuring means to measure similarity between different videos based on characteristic amounts obtained from an “image part” of the videos. However, since similarity is judged only for the image parts, such technologies can fundamentally only be used to carry out judgments of similarity for videos where the content of the image part is substantially the same.
In PCT Application WO2004061711, videos with images that have similar transitions or pictures are recommended to the user, so that the system can be described as a content recommending system that is dedicated to situations where video images are shot with a fixed camera and a distinct pattern is present in the image part, as in video images of sports such as tennis. It is therefore doubtful that such system would be as effective when making recommendations for all types of videos.
In addition, with all of the methods listed above, since no reference is made to the content of the videos, of the methods is suited to recommending videos, such as parodies, where the content is similar but the pictures are different or to discovering illegal videos where the image part is different but only the “audio part” corresponds to non-permitted use of commercial material.
As other methods, Japanese Laid-Open Patent Publication No. 2009-70278 measures similarity between video images using “comments” and Japanese Laid-Open Patent Publication No. 11-308581 (Japanese Patent No. 3569441) measures similarity by searching “text in a program guide” that accompanies programs.
Publication No. 2009-70278 extracts words referred to as “characteristic words” from the content of comments that accompany each video and measures the similarity between videos by comparing the distribution of the sets of obtained characteristic words. The premise here is that a plurality of comments have been assigned to at least a plurality of scenes in all of the videos to be compared. This means that the ability to specify similar videos and the precision when doing so are dependent on the number of comments assigned to the videos being compared. Although it is assumed that there is a high probability of preferred characteristic words being included in comments, since the content of comments is fundamentally freely chosen by users, there is no guarantee that preferred characteristic words will be included. Meanwhile, it is not realistic to implement limitations over the comments that can be made by users.
Publication No. H11-308581 uses program guide information that accompanies a program to measure similarity between a program being viewed by the user and programs that the user can view and that have been assigned a program guide and recommends programs with high similarity to the program being viewed. With this method, videos are recommended based on information that accompanies programs. However, program guides are merely summaries of programs provided by the respective suppliers of videos. Also, in the same way as with Publication No. 2009-70278, since there are no limitations on how such information is written, the number of similar videos that can be discovered by this method is extremely limited, and as a result it is thought difficult to make sufficient recommendations given the great amount of content that is available. Also, since there is fundamentally a one-to-one relationship between program guides and programs, it is not possible with this method to judge similarity between videos in units of scenes.